... (cm–1)PbCrO4 839 (M) 37 8 (vW)Na2CrO4, xH2O 33 40, 32 50 (vH2O) 938 (M), 9 23 (M), 891 (H), 8 53 (vH), 810 (M) 438 (W), 35 0 (W)K2CrO4906 (M), 877 (M), 869 (H), 8 53 (H) 39 4 (vW), 38 9 (W), 34 8 (M)CaCrO4905 ... 420and 37 0 cm–1 (ν2 and ν4).2 6 -3 0Campbell 30 had defined two types of chromates from vibration spectra:1. “Type I chromate” spectra previously described (Na-, Ca-, Ba-, Sr-, Rb-, Li-, Ag-, ... present in the smallest sizes (< ;3. 3 µm). In the context of occupational health, the similarity of distributions of the valency of chromiumas collected by the two impactors at the same site indicates...